The number of electron energy levels in a magnesium atom is ________.
A)1
B)2
C)3
D)4
E)5

Question

Quizplus · Accepted Answer

Magnesium has 12 electrons, which are distributed in 3 different energy levels: 2 electrons in the first energy level, 8 electrons in the second energy level, and 2 electrons in the third energy level. Each energy level has a maximum number of electrons it can hold, based on the formula 2n^2, where n is the principal quantum number of the energy level. Therefore, the first energy level can hold a maximum of 2 electrons (n=1), the second energy level can hold a maximum of 8 electrons (n=2), and the third energy level can also hold a maximum of 8 electrons (n=3).

The Number of Electron Energy Levels in a Magnesium Atom